Product Finder Expert of the Week:Lisa R. Ginn

Pursuing a career in cosmetic dermatology was a way for Lisa R. Ginn to combine her interest in medicine and her passion for beauty products. "I've always had an artistic side and been good with my hands, so it seemed like a great fit," says Ginn. "I also love products. I've thought of myself as a product girl dressed up, playing dermatologist." So Ginn decided to learn everything she could about skin care: "I went and got an aesthetician's license because you don't learn about skin care in [medical] school, and I worked as a medical officer at the Food and Drug Administration's division of cosmetic regulation," she says.

Now, Ginn, who has been a dermatologist for 11 years, practices in Chevy Chase, Maryland, and says that one of the most common skin mistakes she sees among her patients is a tendency to strip protective oils from their skin. "I'm unashamedly biased; I think the skin is the best organ we have, and it asks for so little," says Ginn. "But you do have to invest in it. You could have had problematic skin all your life, and if you find the right person to guide you, you can have great skin in your 40s and beyond."

Here are some of her favorite lessons for keeping your skin in tip-top shape:

Where to spend your money: "Invest in serums. They can be expensive, but they last a long time. Skimp on modestly priced cleansers and moisturizers. You'll get the most dramatic results without really breaking the bank." Ginn likes SkinCeuticals Hydrating B5 Gel serum.

Best-kept secret: "The multi-vitamin complex in IS Clinical Poly-Vitamin Serum tones down rosacea—which I use it for—and treats acne. Usually, it's very hard to treat acne on rosacea prone skin, because it gets dry and irritated, and the redness gets worse. But this serum allows me to treat both issues."